During the past few weeks biologist Tony Musante has been trekking through southwestern New Hampshire in pursuit of the state’s elusive feral swine population.

He has been responding to calls from farmers who have identified the animals’ handiwork — rooting damage in hay fields, gardens and yards — and investigating sightings by hunters who have caught the animals on trail cameras. The calls and leads are the result of a new effort by New Hampshire Fish and Game and the U.S. Wildlife Services, which are asking people to report any sightings of what U.S. Wildlife Services calls the nation’s largest and most destructive non-native mammal species.

“We received some funding, and that trickles down into the state. It gives us the ability to increase efforts toward limiting the population — more manpower and equipment,” Musante said.

The hogs Musante is tracking, with hopes of eventually eliminating, aren’t the small, pink-skinned, domestic animals celebrated in movies like Charlotte’s Web or Babe. These massive mammals can reach 220 pounds and have different genetics than farm pigs. They are often dark-skinned, covered in bristly hair, and considered invasive, destructive and potentially dangerous.

“The most obvious problem is the damage they can cause,” said Musante, a wildlife disease biologist for USDA/APHIS-Wildlife Services. “They root and dig. They can root up whole fields looking for grubs and insects. They also browse native vegetation. … They carry as many as 30 diseases and 37 parasites, which could hurt people, pets, other wildlife.”

It’s unclear how many feral swine are roaming the state, but there are likely a couple hundred. The number doesn’t appear to be changing.

Their scientific name is Sus scrofa, but they go by razorback, wild boar or feral swine — and whatever you call them, state officials want them out.

“It’s an invasive species not native to the northeast of the country,” said Mark Ellingwood, wildlife division chief of New Hampshire Fish and Game. “The long and short of it is it has quite a negative impact because of aggressive feeding. And they reproduce rapidly, have high survival rates and can quickly raise their numbers to high levels in short order. .... No specific predators focus on them.”

They degrade the natural plant system and destroy as much as 1,000 acres per hour. They consume native species of animals too, including amphibians, nesting birds, wild turkey, grouse and young mammals like deer fawn, Ellingwood said.

Another problem is the potential for disease. The hogs have been known to carry swine brucellosis, which can impact reproduction in domestic pigs and cause disease in humans, pseudorabies virus, a fatal livestock and animal disease, and swine fever, which hasn’t been found in the U.S. since the 1970s but could cause mass mortality, Mudante said. So far Mudante hasn’t seen these diseases in the state, but “we did have a positive pseudorabies test in New Hampshire,” he said.

The animal has been most prevalent in Sullivan, Cheshire and Grafton counties. It is the wild native of domestic pigs from northern and Central Europe likely carted to the southern region of the U.S. by 16th- and 17th-century explorers. Nationally, the species’ population is growing significantly, and it’s making rapid inroads from southern states to the north, said Ellingwood.

Most likely, the majority of the state’s population comes from The Blue Mountain Forest Reserve (also known as Corbin Park) historic facility located in southwest New Hampshire established in 1890 by Austin Corbin, who bought up dozens of New Hampshire farms in order to create one of the nation’s largest hunting preserves.

“It was established to preserve specific species, including Russian boar,” Ellingwood said. “They have been grandfathered into the state in ways that result in being able to hold those animals there. Of course, they are escape artists, if you will. Sometimes they get out.”

Since the 1940s, New Hampshire law has listed them as free-ranging private property, the same as escaped farm animals.

“Meaning you have owners’ permission to hunt them,” Mudante said. “But trying to decide who owns them is pretty difficult.”

Licensed hunters can shoot them, though Fish and Game doesn’t endorse it, and anyone is permitted to kill the hogs if they see them on their property to protect their land.

Officials in New Hampshire track and trap the animals; if they are not able to trace the boars to any domestic source, they “essentially euthanize animals if and when that opportunity exists,” Ellingwood said.